Standard allowance for WTP from HKG is 2x23kgs.

Prepaid bag in WT cannot be transfered to WTP but your're Silver so since 1st March you get one extra bag of 23kgs.

Silver also has higher baggage allowance so in the end you can check in:

2 x 32kgs bags (higher weight allowance as Silver benefit)
1 x 23kgs bag (higher piece allowance as Sapphire benefit)